CASPIAN JOURNAL OF ENVIRONMENTAL SCIENCES (CJES)
Year:2014 | Volume:12 | Issue:2 |Papers Count:12

The aim of this study was to provide necessary information on the age, growth and sex ratio of one of commercially important cyprinid species, Alburnus chalcoides in the southern Caspian Sea (North Iran) from 2010 through 2011. 53 specimens of both sexes (males and females) were collected monthly. The samples were transported to the laboratory for further biological measurements and otolith extraction. The maximum and minimum age of A.chalcoides was 4+(FL=26.0 cm) and 1+ (FL= 18.1 cm), respectively. The mean fork length of A. chalcoides was 20.21?0.287 cm; and the sex ratio was 1.0: 2.12. The length-weight relationships calculated for all individuals were as W=0.141TL2.199 (R2= 0.648). Different regressions were prepared between age and morphological measurements of fish and otolith, of which the highest correlation was between age and body length as a linear regression of TL=1.959Age+16.32 (r= 0.66). There was no significant correlation between morphometric measurements ofotolith and fish morphological parameters (p>0.05), and an allometric growth was found with a slope of b=1.926 for the study area.

Ata-Kuh forest, a preserved area within Hyrcanian relict forests, with an area of 700 ha is located in north of Iran. Based on floristic studies from 2011 through 2012, 194 vascular plant species were identified belonging to 143 genera and 66 families. Among our samples, 24 taxa were endemic to Hyrcanian area. The largest families in the area were Rosaceae (10.3 %), Poaceae (9.7 %), Asteraceae (6.7 %), Fabaceae (5.6 %) and Lamiaceae (5.1 %). The genera represented by the greatest number of species were Rubus (8 species), Carex (7 species), Viola and Euphorbia (each with four species). Classification based on life form indicated that geophytes comprise the largest proportion of the plants in the studied area. From the chorological point of view, the largest proportion of the flora belonged to the Euro-Siberian elements (60 taxa, 31.1%). In this study, a comparison was performed between our results and other studies on the northern Iranian forests with respect to life forms and phytochoria. Psilotum nodum is reported here again from a new locality in North Iran, indicating the old Tertiary history of this forest.

In sturgeon aquaculture, where the main purpose is caviar production, a reliable method is needed to separate fish according to gender. Currently, due to the lack of external sexual dimorphism, the fish are sexed by an invasive surgical examination of the gonads. Development of a non-invasive procedure for sexing fish based on genetic markers is of special interest. In the present study we employed Bulked Segregant Analysis (BSA) methodology to search for DNA markers associated with the sex of the beluga sturgeon (Huso huso). DNA bulks (male and female) were created by combining equal amounts of genomic DNA from 10 fish of both sexes. A total of 101 decamer primers associated with the sex-specific sequences in non-sturgeon species was used for targeted screening of the bulks, resulting in 2846 bands that all of them were present in both sexes. Our results showed that sex chromosomes are weakly differentiated in the sturgeon genome and comprised sequences not complementary to the sex-specific primers in non-sturgeon species.

The genetic structure of the genusAlburnus is not well known and the phylogenetic relationships among its species are uncertain. In the present study, simple sequence repeats (SSRs or microsatellites) were used to evaluate genetic diversity and genetic differentiation between Alburnus mossulensis Heckel, 1843 from Kashgan River in Lorestan province and A. caeruleus Heckel, 1843 from Gamasiab River in Kermanshah province. Thirty specimens from each species were collected and their genomic DNA was extracted. Polymerase chain reaction was performed using four pairs of SSR markers, including CypG24, BL1-2b, BL1-98 and Rser10, from which a total of 480 bands were amplified. The average observed and expected heterozygosities for both species were similar. In both species, except for Rser10 locus, all loci deviated from the Hardy-Weinberg equilibrium (P< 0.05). Average genetic distance andFst values between the two species were 0.361 and 0.04, respectively.Analysis of molecular variance (AMOVA) revealed more interspecific (94%) than intraspecific (4%) genetic variation. Although four sets of SSR markers developed for other cyprinids showed high level of polymorphisms in the Iranian bleaks, they showed low genetic differentiation between them. Study on the possibility of genetic differentiation of the examined species by more microsatellite loci or other molecular markers such as amplified fragment length polymorphisms (AFLP) are recommended.

In the present study, air quality analyses for ozone (O3) were conducted in Ahvaz, a city in the south of Iran. The measurements were taken from 2009 through 2010 in two different locations to prepare average data in the city. Relations between the air pollutant and some meteorological parameters were calculated statistically using the daily average data. The wind data (velocity, direction), relative humidity, temperature, sunshine hours, evaporation and rainfall were considered as independent variables. The relationships between concentration of pollutant and meteorological parameters were expressed by multiple linear and nonlinear regression equations for both annual and seasonal conditions using SPSS software. RMSE test showed that among different prediction model, stepwise model is the best option. The average concentrations were calculated for every 24 hours, each month and each season. Results showed that the highest concentration of ozone occurs generally in the afternoon, while the least concentration is found at the beginning of the morning. Monthly concentrations of ozone showed the highest value in August, while the least value was found in October. The seasonal concentrations showed the highest amounts in summer.

Toxicity tests are commonly used as a tool to determine the standards of water quality for chemicals and to discover appropriate organisms as bioindicators in toxicological studies, and also could be used as an essential tool for evaluation of the pollutant effects in aquatic ecosystems. The aim of the present study was to evaluate the sensitivity of two Caspian fish species, Caspian trout as an endangered species and Caspian Kutum using the static acute toxicity in response to nonylphenol, which is widely discharged into the Caspian Sea environment. The fish were exposed to various concentrations of nonylphenol for 96 hours to determine the LC50. The experimental nonylphenol concentrations were consisted of five exposure groups for each species: 100, 150, 200, 250, and 300 mg/l for Caspian trout; 400, 800, 1200, 1600 and 2000mg/l for Caspian Kutum, with a control group for each of them. Using probit analysis, the 96 h LC50 of nonylphenol to Caspian trout and Caspian Kutumwas determined to be 204.78 and 1262.36 mg/l, respectively. In addition, Caspian trout was approximately 6 times more sensitive than Caspian Kutum.Nonylphenol was reflected to be "highly toxic" to Caspian trout and "moderately toxic" to Caspian Kutum.The results could be considered in preparing plans for conservation and restocking management of Caspian Kutum and the endangered Caspian trout.

The aim of this study was to develop an optimal sustainable forest plantation based on goal programming and Analytic Hierarchy Process (AHP) methods. This study was carried out in Guilan province, north of Iran. First of all, the ecological capability of the study area for plantation establishment/maintenance was evaluated based on multi-factor method and specific ecological Makhdoum Model by means of GIS tools.Then goal programming approach as a multi criteria optimization technique was used for optimization.Therefore, ecological, economic and social aims were considered. Carbon sequestration was chosen as an ecological criterion. To estimate the total aboveground biomass and carbon content stem volume, stem biomass and crown biomass were measured using allometric equations. The net present value was also calculated using stumpage price, harvesting cost, consumer price index, annual growth, interest rate and optimal rotating. Estimated required labour for different plantation items were obtained from data base of Iranian Forests Rangelands and Watershed Management Organization. In order to achieve all purposes simultaneously, the goal programming technique was applied. Results indicated that using mathematical modeling provided a more logical set of consequences compared to using ecological modeling. The ability to change the weighting of the variables in the mathematical equations enabled decision makers to choose the optimal solution. Final results indicated that the appropriate plantation area for each species are as follow: Acer velutinum (810 ha), Alnus subcordata (348 ha), Pinus taeda (235 ha), Tilia begonifolia (165 ha), Quercus castanifolia(149 ha), Pinus nigra (110 ha) and Fraxinus excelsior (0 ha).

This study was investigated the effects of dietary estradiol-17b (E2) on growth, body composition and blood indices in Acipenser stellatus. Fish (40.9 ± 1.1 g average initial weight; n=60 per group) were fed with three different diets containing 0 (control), 25 and 50 mg kg-1 dietary estradiol contents to apparent satiation for seven months. The results suggested that growth rate were decreased as the E2 level was increased. No significant difference was observed in condition factor among dietary treatments. The highest survival rate was observed in fish fed control diet, but was not significantly different among the treatments (P>0.05). Body composition did not show significant changes among dietary treatments. Number of white blood cells and red blood cells, hemoglobin and hematocrit values were significantly decreased as the E2 levels were raised (P<0.05). Plasma biochemical parameters including glucose, total protein, cholesterol, triglyceride, calcium and phosphorus levels were dose dependent with the lowest levels in control with the highest levels in fish treated with 50 mg E2. The results of the present study revealed growth suppression of dietary E2 and changes of blood indices with providing some basic information on the effect of estrogen hormone on physiology of sturgeon.

Afforestation of contaminated areas is considered as a possible strategy for reduction of contaminations. In the present study, the effects of lead (Pb) and cadmium (Cd) were investigated on chlorophyll fluorescence parameters (Fv/Fm, Fo, and Fm), photosynthetic pigments (chlorophyll a, b, and total chlorophyll), and proline in one-year-old seedlings of Celtis caucasica and Robinia pseudoacacia. The seedlings were treated 2 times during 10 days, with different concentrations of Pb and Cd (0, 250, 500, 1000 and 2000 mg L-1). Saline solutions containing Pb and Cd were sprayed on the leaves. Chlorophyll fluorescence was measured every other day. Chlorophyll and proline were also measured at the end of experiment period. The results indicated that chlorophyll fluorescence of C. caucasica and R. pseaudoacacia was affected by Pb on the last days and by Cd on the first days. The chlorophyll a content of C. caucasica at 250 mg L-1 of Pb and the chlorophyll a of R. pseudoacacia at 1000 and 2000 mg L-1 of Cd increased. With increasing Cd and Pb concentrations, proline of C. caucasica increased significantly while proline of R. pseudoacacia was not affected by Cd and Pb. Our results suggested fairly similar photosynthetic responses of C. caucasica and R. pseudoacacia to Cd and Pb concentrations. We concluded that physiological sensitivity of the both species to Pb and Cd were weak and can be used for afforestation in semi-arid areas contaminated by Pb and Cd.

This study was accomplished to examine the efficiency of natural zeolite in preventing acute toxicity of total ammonia to Huso huso. The study was performed using Water Static Method in 96 hours. Fish averaged 46 ± 5 g in weight and 22 ± 4 cm in total length were exposed to four different concentrations (15, 30, 50, 75 mgL-1) of ammonia and a group was considered as control. Under stable condition, the lethal concentration of ionized ammonia was 75 mgL-1 in 96 hours. In the lethal concentration of total ammonia, different amounts of 5, 10, 15 g.L-1 granulated clinoptilolite zeolite were used. Results indicated significant differences between treatments and control (p<0.05). By increasing Clinoptilolite zeolite in each treatment, the survival rate of fish also increased significantly (p<0.05). In lethal concentration of ammonia, the use of 15 g.L-1 zeolite could prevent the mortality rate. Histopathological findings showed that major lesions in gill filaments included hemorrhage, hyperemia, hyperplasia, epithelial cells necrosis. There were hemorrhage, hyperemia, degenerated tubules of kidney, expansion of Bowman's capsule in kidney and hepatocytes necrosis in liver.

Persian sturgeon, Acipenser persicus is a native, commercially important and highly steemed fish species in the Caspian Sea. In this study, effects of Nodularin (NODLN), a cyclic pentapeptide hepatotoxin, on liver and gill tissues of A. persicus were studied. Nodularin was produced in high amounts by Nodularia spumigena, a cyanobacterium species during the algal bloom in the Caspian Sea and was accumulated in biota of the Sea. Persian sturgeon were exposed directly to NODLN as prolonged immersion containing N. spumigena in two different doses (1×104 and 1× 108 cells.ml-1) for 24, 48 and 96 hours to examine its histopathological effects on fish liver and gill. Histopathological examinations revealed loss of liver architecture, degeneration of hepatocytes, nuclear pyknosis, karyolysis and finally necrosis of the cells over the time. Observation of gill tissues following immersion in algal cells treatments showed hypertrophy, fusion of secondary lamellae due to proliferation (hyperplasia) of branchial epithelium in low dose and vacuolization of epithelial and pilar cells, tellangiectasis, fusion of secondary and primary lamellae, complete necrosis and sloughing of secondary lamellar epithelium in high dose.

The distribution and abundance of high aquatic plants in the Gorganroud River was examined at five stations in four seasons (20 samples) over one year period during 2009-2010. We identified 21 species of aquatic plants from 21 genera, belonging to 9 families. These species were determined as 3 halophytic species (14.2%) and 18 high aquatic plants (85.7%).The highest species diversity was observed at Khajenafas, Aq qala and Chargoli stations (17, 13 and 11 species) respectively, The highest biomass of high aquatic plants were recorded in summer (for Inspection and Chargoli stations 11.5 and 10.1 g.m-2, respectively) and autumn (for the station of Inspection was 8.5 g.m-2 dry weight). The most dominant species were different in the investigated stations. At station 1 species Tamarix kotschyi, at station 2 species Juncus acutiflorus, at station 3 species Hordeum murinum hudson, at station 4 species Salicornia europaea L and at station 5 Juncus acutiflorus species were dominated.